Observer News: Divers swim back in time in North Port spring
Divers swim back in time in North Port spring
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Mitch_Traphagen on 26/08/2010 18:48:32
By MITCH TRAPHAGEN
mitch@observernews.net
Dr. John Gifford prepares to dive to the 90-foot deep ledge at Little Salt
Spring. Mitch Traphagen photos NORTH PORT, FL — Just a few miles from the
constant din of Interstate 75, and only a short distance down a two-lane road
with a convenience store and strip mall, lies a portal to Florida’s ancient
history. To the casual observer, it would appear to be a pond surrounded by
scrub palms and white oak trees. In all likelihood, it looks much the same today
as it did over 100 years ago.
But go back 100 centuries and there would be a different story to tell. The
pond, known as Little Salt Spring in North Port, is a sinkhole. Ten thousand
years ago the water level was approximately 90 feet lower than it is today
revealing a dry ledge. Today, that ledge has the potential to yield what could
be a very rare vault of artifacts from our distant human ancestors.
“In archeology you never say you found the earliest of anything because
somebody can go out and find something from a little bit earlier,” said Dr.
John Gifford, a marine archeologist with the Rosenstiel School of Marine and
Atmospheric Science at the University of Miami. “Essentially, we’re looking
for evidence that pushes back humans being here a few thousand years. We brought
up three items just now from the 90 foot ledge at Little Salt Spring. These have
undoubtably been underwater for 9 or 10 thousand years.”
The same elements that attract snow birds and tourists to the Sunshine State
have also erased much of Florida’s history. The sunshine, heat, humidity, salt
water and salt air make archeology a challenge in this state. History literally
dissolves here.
Gifford was part of a three-man team that dived 90 feet to the ledge last
Thursday. At that depth, it is dark and even the slightest movement disturbs the
sediment that has collected over the millennia. Visibility is a problem and
extreme care is required in handling the ancient and very delicate objects. The
team returned to the surface with three potential artifacts. The first piece is
the jawbone of what they believe was an immature whitetail deer, the other two
were wood objects. The items represent a small sample of what the scientists
believe the ledge may yet yield.
Little Salt Spring in North Port, is a sinkhole
“Deer are very common in Florida and they were here at the end of the last ice
age, as well,” Gifford said holding the piece of bone, still containing teeth.
“This particular deer was obviously not diving down to 90 feet. It may have
fallen into the hole when the water level was 90 feet below its present position
and made it to the ledge. There are some marks on here we’ll have to look at
carefully, it appears they were made by small rodents that were eating away at
the carcass but I’m not sure yet, we’ll have to get a specialist to take a
look at it.”
The other two pieces, however, may yield clues to what the researchers are
looking for.
“This is a very non-natural shape,” said Gifford as he held a small, round
piece of wood. “I wouldn’t go quite as far to say it is an artifact yet but
after we clean it up a bit and look at it under a microscope it may show some
marks or shavings made by a stone tool which would indicate that it had been
artificially modified and therefore is an artifact. But it does look very
suspicious. The fact that it was found very near the deer jaw is also
suspicious.”
The third piece is even more suspicious.
“The interesting thing about this piece is that it has a pencil point on
it,” Gifford continued. “That is not usually the case with the branches that
we find. It may have been sharpened by people. We’ll have to take a very close
look at it under a microscope.”
That the wood survived at all is nearly a miracle. Mitch Traphagen Photo Dr.
John Gifford, underwater archeologist from the University of Miami, along with
divers from the Florida Aquarium, brought up three objects, estimated to be at
least 10,000 years old, from Little Salt Spring in North Port last week.
Pictured is a wooden item that may have been sharpened by early humans.
“The unique aspects of Little Salt Spring are that it is a sinkhole and it
also has water flowing out of it, so it is a flowing spring. The water that is
flowing out is coming from thousands of feet beneath the earth’s crust. It has
been underground for so long that there is no dissolved oxygen in it. It’s
anoxic. You would not normally find a piece of wood that is nine or ten thousand
years old because it would have decomposed but this has survived because the
water has no bacteria, basically.”
Gifford went on to say that stone tools are rare in Florida because there was
little workable stone with which to make tools. Wood and shells were the
materials of choice.
“This would be the first evidence in South Florida of early human
occupation,” Gifford said. “In North Florida some Mammoth bones have been
found with cut marks. We don’t have human remains or stone tools but we have
these bones that have been worked, which is circumstantial evidence for people.
That has been dated to about 12,000 radio carbon years.”
Learning about human history is a challenge that goes beyond environmental
concerns, as Gifford pointed out.
“The interesting problem that we face is the further back you go in time, the
fewer people that were here,” he said. “So even in the best of circumstances
there are going to be fewer traces of their activity so Little Salt Spring is
one of those places where we have at least a fighting chance of finding some
traces of human activity from nine or ten thousand years ago whereas the other
99.99 percent of the land surface here, there is simply no trace at all.”
Little Salt Spring was first discovered as an archeological site in the 1950s.
Until last week, the most recent excavation took place in the 1970s, yielding
bones from a mastodon, a tortoise and a giant sloth. The site, donated to the
University of Miami in 1982, is believed to hold some of the most important
archeological treasures in Florida, if not in the nation. Excavating the site,
90 feet below the surface, is painstaking, expensive and dangerous.
“Everyone finds this incredibly interesting but it’s not high on anyone’s
list of priorities for funding,” Gifford said.
Scientists returned to the site in 2008 with a grant from the National
Geographic Society. Last week’s dive was made with the assistance of the
Florida Aquarium in Tampa. Gifford is confident their work will pay off and that
the ledge will lead to answers to long-unanswered questions.
“I think when we finish our analysis and work on publications, what we have
found will get into textbooks,” he said.
For complete video coverage of the dive at Little Salt Spring, click here.